Pipeline union couplers, pipeline union record fittings and other couplers associated with filters, pumps, valves, pipes, etc., have long been used in pipes, such as water lines, fuel lines, chemical supply lines, etc. Couplers typically clamp together two planar or frusto-conical annular surfaces with or without O-rings. The term “coupler” will be used to encompass all such couplers and fittings, such as union record fittings.
One of the problems in coupling pipes with other fluid fittings is that the pipe may be cantilevered with respect to the fluid fitting. The weight of the cantilevered pipe exerts a moment on the fitting and coupler and can tend to apply a bending moment on the coupler located at its root. There can also be angular and/or axial misalignment between the pipe and fitting or coupler.